[a-b]=[a]-[b]

Solution for [a-b]=[a]-[b] equation:

Simplifying
[a + -1b] = [a] + -1[b]

Remove brackets around [a + -1b]
a + -1b = [a] + -1[b]
a + -1b = a + -1[b]

Add '-1a' to each side of the equation.
a + -1a + -1b = a + -1a + -1b

Combine like terms: a + -1a = 0
0 + -1b = a + -1a + -1b
-1b = a + -1a + -1b

Combine like terms: a + -1a = 0
-1b = 0 + -1b
-1b = -1b

Add 'b' to each side of the equation.
-1b + b = -1b + b

Combine like terms: -1b + b = 0
0 = -1b + b

Combine like terms: -1b + b = 0
0 = 0

Solving
0 = 0

Couldn't find a variable to solve for.

This equation is an identity, all real numbers are solutions.